Keyboard tray



FIG. 1 is a top perspective view of a keyboard tray illustrating the ornamental design;

FIG. 2 is a rear elevational view;

FIG. 3 is a side elevational view of one side;

FIG. 4 is a bottom view;

FIG. 5 is an opposite side elevational view thereof; and,

FIG. 6 is a front elevational view. 

The ornamental design for a keyboard tray, as shown. 